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[KB5ZCR]

Howdy all, first off, I'm new to aprs.
I would like to connect my mobilinkd TNC2 to an old Kenwood TM 241a.
I have downloaded the pdf tnc2 manual from their website.

I'm going to have to make my own cable between the tnc2 and the kenwòod.
It seems pretty straight forward.

Has anyone ever wired one of these to an old 2 meter radio, if so did you run into any issues.
I do think I will need to make some of the connections to the radio mic connector and also to the external speaker jack for audio out (and audio in for the tnc2).

Any help full tricks or issues you ran into would greatly appreciated.

Thanks, Tim DE kb5zcr

[NA4IT]

Not sure if your older radio would have a phantom or bias voltage on the mic audio line. If so, you might need a DC blocking capacitor. You can probably look up your mic jack wiring and find out.

You might also need a voltage divider circuit to cut some of the audio coming out of the speaker jack. Take a look at some sound card interface diagrams and you'll see the circuit. It looks like a couple of resistors in a "T" configuration.

I like hearing of hams actually doing projects. IMHO that's a big part of ham radio.